The exhibit’s three females and two males had lived together for the last three years.

Zoo officials say were moved to another enclosure after the attack and won’t be in the exhibit with any other lioness for now.

“I’ve been in the zoo business for over 35 years. I’ve worked at five major zoos, and I’ve never seen a cat kill another cat before,” Lynn Kramer, vice president of animal operations and welfare at the Dallas Zoo, tells NBC-DFW Channel 5.